Automatic telephone system



0.- S.. "HUL'FI"SH. AUTOMATIC- TELEPHONE SYSTEM.-

APPLICATION 'F'ILED MAY 21. 1919.

Patented May 30, 1922.

ISHEETS-SHEET l- D. S. HULFISH.

AUTOMATIC TELEPHONE SYSTEM.

"APPLICATION FILED MAY 27, I918.

Patented May 1922.

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APPLICATION FILED MAY 21,4918.

Patented May 30,1922.

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Patented May 30, 1922.

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Patented May'30, 1922.

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AUTOMATIC TELEPHONE SYSTEM.

APPLICATION FILED MAY 27. 1918.

Patented May 30, 1922.

I SHEETS--SHEET 7- plate 209.

nsures stares i PQATENT OFFICE-Q DAVID s. nniirisn, or ronouro, ONTARIO, CA ADA.

AUTOMATIC rnrnrnonnsystrmvr.

T 0 allwlzomdt may concern. l

Be it known that}. DAVID LlULrisI-r, a citizen of the United States {it .fimerica, residing. at Toronto, in the county of York and Province of Ontario, Canada, have in vented new and useful Improvements in Automatic Telephone Systems, of which the following is a specification.

My invention relates to iiiiiprovements;in

automatic telephonesystems and the objects system of circuits for giving telephone service.

Referring to Figs. 1 and 2 :The movable brushes 201. 20.2 carried by insulation upon brush shaft .203 engagethe under surfaces of eligible contacts 204-, held fixed in the con tact banlrnpon insulating plate 206. The contact bank comprises a plurality of levels of contacts, many known methods of construction being? available. Each level has two'brushes asshown. each brush having a feed vcontact 205 fixed in the Contact bank". The feed contacts are :in the level of the eligible contacts. The brushes shown, 201 and 202, engage the under surfaces of the feed contacts as well as ottlieeligible contacts, hence the brush inaiypass the feed contact. Alternate vlevels. have. brushes above instead of below; The contactbank comprises contact-bank plates 206-land contact-e204, 205, rigidly held together and attached to fixing plates 207,-the fixing plates being then fixed upon verticalsupporting raclrbars 20S. Dowels255 are lined in parts 207 and pass throughholes 'in switch body- The faces of parts 207 engage the back face of part 209.

Body plates 209 has flanges 210 lormed integrally therewith and supporting brush carrying shaft 203 and armature shaft 211.

The brush carriage comprises shaft 203, hub

212. ratchet 213 brush spacers 214 of insu lation, teed-contact. guides 215 of insulation,

brushes 201, 202, clamp 216, and screws 217 which-thread into hub. 212 and clamp all 7 Specification of Letters Patent.

Application filed ma 27, 1918.. Serial No. 236,833.

shows section of Patented May 30,1922.

parts. The alinement of brushes is attained by insulating dowels 218.

Main spring 219 attached to hub 2l2 and flange 210 turns brushcarriage when double pawl 220 permits and the brushes pass from contact to contact, advancing a half-step when armature 221 has been attracted and the remaining half-stepwhen armature has been returned to normal. byarmature spring 256. A brush may be shaped to engage a contact while the armature is normal or while the armature 1s attracted, or both. A

brush at one end of its travel may rest. upon its own feed contact. Arn'iature carrier 222, carrying armature 221 and double pawl 220, is carried by armature shaft 211 between spacingsleeves 223, and, is pulled by spring 256. Magnet support 224 supports magnets 225 and-clutch-arm guide 226. Clutch arm 227 is pivoted upon ratchet 213, rests upon wing 228 of guide 226 and is drawn against.

the guidehy spring 229. Clutch tooth or thrust member 230 is clamped upon drive shaft 231. tinually through a predetermined angle. Normal switch 232 comprises two contact sprin mounted upon bracket 233 uponsupporting bar 208, tending to open, he l-d closed by part 226 and spring 234. Clutch arm 227 is shown in three positions, solid line in nor mal position, dash line awaiting restoration, and dot-dash line'at close ofthrust of clutch hook. Parts 230 and 236 are shown in dotdash line in their positions at the time part 227 occupies its dot-dash position.

The-operation oi the swnch 18 as follows:

Repeated electrical currents through magnets 225 operate armature 221; repeatedly and the brush carriage moves step-by-s'l'iep until a desired selective position attained. For restoration tonornial, 'l'urthjer repeatedor intermittent currents operatethe armatin'e, the brush carriage moves. the clutch arm 227. propelled by ratchet passes its corner 235beyondguide 22.6, and spring draws the clutch arm into path of clutch tooth 230, as shown in dot line in Fig. The clutch tooth engages the clutch arm and forces the clutch arm to position shown. in dot-dash line in Fig. 2, thus restoring the brush car-- riage to normal. The clutch-arm corner 235 has forced guide 226to position shown indot-dash line. thus opening normal switch as shown indot-dash line. Tooth 230 retires and dlsengages itself from arm 227,

spring pullsguide 226 to normalposi Drive shaft osci]lates'con- I I 1,418,187 I tion, closes normal switch 232 and lifts arm 227 to normal position as shown in solid line.

I By determining the dimension of the double pawl 220 between the faces which engage the ratchet, the relative lengths of the first and second steps of the ratchet and brushes "for each ratchet tooth may be determined.

The devices for driving the shaft 231 are as follows: Motor 236 (Fig. 3) drives power wheel 23?, link 238 and driving arm 239 upon shaft 231; The shaft 231 oscillates continually as indicated by the double-head curved arrow.

Switches of the type described may be organized by electric circuitsfand associated with telephones and callsenders to give an automatic telephone service. A system of circuitsis shown in the drawings, thefigures uniting at the margins where conduc-.

tors of similar labels meet. Each switch has contact-levels sufficient in number for its requirements, the levels being numbered at the ends. The contacts'ineach level are numbered below. Each contact is represented by a circle each brush by a rectangle united by a-conductor-line to its feed contact.

A brush shaped to engage one contact but not two contacts at the same time is shown by a rectangle, as 10370. A brush shaped to engage two contacts at the same time, thus holding unbroken connection with aseries of contacts, is shown by a'longer rectangle, as 1036'-0. A brush shown be- 35 tween. contacts will engage a contact at the halt-step, as 10L-'50 and 104--60. A brush shown in an advanced position-upon a contact, as '1031 1-25, will break from the contact at half-step, its engagement at haltstep with the succeedmg contact being immaterlal. A brush shown in a retarded.

position upon a contact. as 1031325, will not engage the succeeding contact at half- .step, its break at halt-step from the preced ing contact being immaterial. 'A' pair of staggered brushes, as 103 13 25 and 103.-1125, upon contacts connected in pairs as shown. will be be connected together at full step. This arrangenient off brushes facilitates adjustment for interruptions at half-step or full-step.

The callsender may be of any known type,

the electrical contact members being arranged as required. I I

' In the drawings, numbers under 30 are location numbers for identifying. contacts.

A contact is identified by giving first the label of the switch, then the level number,

1032-6, meaning switch 1.03, level 2, conthen the contact number in the level; thus,

tact 6. A brush is identified by the location of its teed contact. Theposition ot'a switch, or of the brushes in the switch, is

I identified by giving two occupied contacts;

being I I disconnectedfrom each other at halt-step and will thus in the diagram the pilot is shown store from 11and23 to 0.and12. This variation is attained by adjusting the setting of the hook 230 on shaft 231, by the setting of stops and springs of 232 as atl'ecting guide 226 and by predetermining in manufacture the length of clutch arm 227. I

. The automatic switches are grouped into sets or divisions which are duplicated as required to serve the traflic. I or primary set of swltches comprises 1st .pilot 103, groupfinder .102, linefinder 101,

A 1st; set

1st register 104:, and 1st searcher 105. A

'2nd set or interconnector set comprises 2nd pilot 106, 2nd register 107 and 2nd searcher 108. A final set comprises final pilot 101, final register 102 and final con- 1 nector 403.

The 1st set finds the calling line, registers the 1st digit called for, anol finds an idle 2nd set. The 2nd set or first interconnector set registers the 2nd digit called for and finds an idle final set. The final setregisters the last two digits called for and sends a completion signal and a ringing starting signal to 1st pilot which their rings, registers and releases. Additional interconnec- Set and the final set to increase the total number of lines served.

Each telephone line'h'as two relays, line relay 130 and cut-ofl' relay 131 constituting a relay set fortelephone 156, having directory number 36. Line relays, as 130 and 1302, which pertain to the same half-level ot the linefinder 101, are grouped ,upon a common wire, as 318 .or- 319, extending to the grouptinder 102, identifying the groupfinder position for those lines. Line relays,

torsets may be connected between the 2nd as 1302 and 1303, which pertain to the same I linefinder position, are grouped upona similar common wire, as 316 or 317 identifying the linefinder position for those lines.

Circuit-s are referred to by numbers, C1,

C2, etc. I

The operation is as follows:' 1 A lifted receiver at'telephone 156 by its hookswitch closes C1 and charges line relay 130. Then line relay 130 by (11.1 charges starting relay 132. 4

01. Line. Battery, helix of 130, points starting relay 132, wire 389, points of line relay 130, earth.

Starting relay 132 closes C2 to char 'e linelinder magnet 121 repeatedly and 2.1 to charge grouplinder magnet 122 repeatedly, these circuits being interrupted respectively by brushes 101-18-25 and 102-6-25 at the half-step, until test brushes 101-18-0 and 102-(5-0 close searching circuits C3 and U31, respectively. C3 then charges relay 42 which opens (12; and C31 charges relay 44"which opens 02.1. Relays 42 and 44 jointly close ()4 to charge the pilot magnet. Pilot brushes pass to position 2-14.

()2. Linefinder drive. (Pilot 1-13.) Battery, linelinder magnet 121, normal switch 111, brushes 101-18-25, 101-17-25, 101-16-25 and contacts 12-to-23, Wire e07, 103-12-1, 1025-11-1, wire 306, relay 42 points, wire 305, 103-11-13, wire 304,

relay 132 points, earth.

(12.1. Groupfinder drive. (Pilot 1-13.) Battery, grouplinder magnet 122, normal switch 112, rushes 102-6-25, 102-5-25, 102-4-25 and contacts 12-to-23, wire 310, 103-10-1, 103-9-1, wire 309, relay i 44 points, VVllG 30s, 103 13-1, 103-14-1, 1103-11-13, wire 304, relay 132 points. earth.

(13.Linefinder test. (Pilot 1-13.)

Battery, relay 42 helix, wire 314, 103-9-13,

1023-10-13, wire 315,101-18-6, wire 317, relay 130 points, earth.

(13.1. Groupfinder test. (Pilot 1-13.) ."iattery, relay 44 helix, wire 320, 103-7-13, 103-8-13, Wire 324, 102-6-3, wire 318, wire 389, relay 130 points, earth.

C4. Pilot magnet. (Pilot 1-13.) Battery, pilot magnet 123, normal switch 113, 1023-18-13, 103-17-13, 103-16-13, wire 327, relay 44 points, wire 326, 103-6-13, 103 5 13, wire 325, relay 42 points, wire 305, 103-11-13, wire 304relay 132 points, earth.

iVith pilot in position 2-14, C5 charges relay 42 (relay 41 remaining uncharged) and C6 charges pilot magnet 123. Pilot passes to position3-15. 1

C5. Loop test. (Pilot 2-14.) Battery. relay 42 helix, wire 314,1.03-5-2, wire 111, 102-1-3, 101-13-6, wire 361., Wire 301, telephone 156. wire 302, relay 131 points, earth. 1

C6. Pilot magnet. (Pilot 2-14.) Battery, pilot magnet 123, normal switch 113, 1113-14-14, 1024-13-14, 1053-12-14, Wire 33-1, relay 41. points, wire 330, 10 3-6-14, 103-5-14, wire 325, relay 42, points, wire 305, 1053-11-14, wire 304, relay 132 points, earth. I

iVere lines 156 (groupfinder 3 linefinder 6) and 1563 (grouplinder 8 linefinder 3) waiting contemporaneously with relays 130 and 1303 charged and earth on indicator wires 31?, 313, 319, linefinder 101 would stop on 101-18-3 for line 1562 (groupfinder 3 linefinder in error; then with pilot 2-14, either (a) with line 1562 idle C5 would not be formed to charge relay 42, and C2 would drive linefinder 101 further, or (b) with line 1502 busy, (15.1 would charge relay 41, and (15.2 would drive linelinder 101 further. Thus .12 and (15.2 alternatively would drive the line linder 101 to 101-18-6 for line 156, where relay 42 would charge and relay 41 would not charge and C6 would be formed to advance the pilot to 3-15.

(15.1. Guardtest. (Pilot 2-14.) Bab tery, wire wire 363, 1111-15-11,

102-3-3, wire 313, 103-4-2, wire 320, relay 41 helix, earth.

115.2. iiinetinderdrive. (Pilot 2-14.) Battery, linetinder magnet 121, normal switch 111, brushes 101-18-25, 1111-17-25, 101-16 2.), and contact 12-to-23, wire 30?, roe-1342, 1021-14-2, wire 335, relay 41 points, wire 330, 1113-6-14, 103-5---14, Wire 325, relay 42 points, wire 305, 103-11-14, wire 304, relay 132 points, earth.

With pilot in position 3-15, C? charges cut-oil relay 131 and C8 charges calling teed relay and signal relay 41. 015.1 charges pilot magnet 123 and pilot brushes pass to posltion 4-16. I

Ci. Calling guard. (Pilot 3-15.). Battery, resistance 1.34, wire 336, 1.03--43, wire 313, 102 3-3, 101--15--0, wire 3653, relay 131 helix, earth.

C8. Calling loop. (Pilot Battery, relay helix, wire 31.4, 103-5-3, wire 311, 102-1-3, 101--13-(i', wire 361, wire 301, telephone 156, wire 302, wire Ii01-146, 102-2-3, Wire 312, 103-6-3, wire329, relay 41 helix, earth.

(16.1. Pilot magnet. (Pilot Battery, pilot magnet 123, normal switch 113, 103--14-15, 103-l.3-15, 103- l2-15, wire 335, relay 41 points, wire 330, 103-2-15, earth.

The next action is to adjust the 1st register or thousands switch 104, to the numerical position required to select ultimately the desired line to be called, by control ot the callsender at the telephone, and then toshift the pilot brushes as "a changeover switch by joint control oi the signal relay 41, the register 104 and the changeover relay 45.

The callsender when operated moves 151 41 sends by C10 set of impulses to changeover relay 15; and switch 104- also sends by C101 and C102 two sets of impulses to relay 4:5, the three sets of impulses being concurrent but out oi? phase so that the points 01- 45 are held operated until after impulses cease in C9 and C10. W hen 4:5'is final y released it closes C11 to charge the pilot magnet.

An impulse in C10 ceases when 11 is re charged but the first companion impulse in C101 continues until after 124. in C9 has been magnetically discl'ia-rged, until alter armature 221 of 124: has been released and retracted to permit dog 220 to clear "from tooth oi ratchet 213, and until inaii .,;'i11,g 219 has moved the brushes as a mass so far that brush 10 1--6-0 has broken contact from its contact; this suciession in time in the termination of the two compauimiinapulses I am describing briefly by saying that the impulses are concurrent but out o1 phase. A'iter this, when brushes oi 104 move still further, brush 10l--1-0 engages its next contact and sends a second ci'nnpanion inipulse over (110.2 to charge 4:5 Further. The two relays 411 and 415 are preferably alike in mechanical construction, the delay by phase displacement of the impulsesto 4.5 heing such that, in. a series of signals, 41-1 is redischarged to re-charge 45 beiore 415 can close C11 and operate the pilot switch. The

current throiiigh C102 charges the changeover condenser 53 which subsequently is discharged by C103. The greater the capacity, of the changeover condenser 52".. the g will be the effect upon the changeovei relay 415. To avoid large currents in the change over condenser discharge, a resistance 54 is included in its circuit.

C9. Numerical. (Pilot 4-- 1(3.) Hattery, register magnet 124, normal switch 114:, wire 338, 103-5-10, l0 --(5-.10,' wire 3 341,

si nal relay ll, points, wire 23230, .l0I-l2 -1o,

wire 8 10, changeover relay 45 points, wire 3'14, 104-5-16 (or as adjusted), earth.

Pilot brushes move to 5-17. With pilot 103 at 5+17, searcher 105 finds an idle interconnector set. C12 and C121 charge searcher magnet 125 to advance the brushes of until test relay 43 is charged by C18 when C1321 charges pilot magnet'123, and

adjusted, brush -180 moving to an idle trunk, 105-18- Z1l, Wire 9533-, 10818-12, 107-312, 106-41-1, helix of ilnterconncrtor holding relay 182, battery, earth.

Cit-3.1. Pilot magnet. (Pilot 517.) Battery, pilot magnet 123, normal switch 113-, 1031417, [03-13-47, 1 03-12*17, Wire 3354-, relay 4:3 points, wire 356 102-l4:-17, earth.

Pilot 1.08 passes to position 6-18, substitutes earth oli 108-3-6 For relay 43 in C13, and awaits completion signal over C23. Relay 182, the interconnector holding relay, is charged but has no effect beyond lighting the inter-connector pilot la1np'162.

The cert action is to adjust the interconnector register or hundreds switch 107 to the numerical position required, by control ol the callsen-der at the telepl'ione, and then 1 to shi 't't the brushes of the interconnector prlot 106 as a changeover switch by joint control of: the signal relay 451., the register I 07 and the 'i-nterconnector changeover relay- 183. 'llhemethod is the same as in ad usting the first register.

The callsender releases signal relay 41 several. times rapidly. Relay 4:1 closes C14: repeatedly which adjusts switch 107 numerically, while by branch circuit C141 a set of impulses is sent to changeover relay 1,83. Switch 107 also sends by C142 and C143 two sets of impulses to relay 183. C1 14 discharges condenser 184:. When relay 183 is finally released, it closes C15 and charges i nterconnector pilot magnet 126, passing interconnector pilot brushes to 2 -14.

C14. Numerical. (1st pilot 6-18; 2nd pilot 1-13.) Earth, 1103- 2-18, wire 330, points of signal relay 11, Wire 2334, 103-1-6, wire 321, switches 10 1,10?) as adjusted, wire 331 106'1-1, wire 384, normal switch 117,

inter-connector register magnet 127, battery, earth.

C141 Changeover relay. (1st pilot 6-18; 2nd pilot 1-13.)- Earth, 1032-18,

wire 330, points of signal relay 41, wire 334, 103-16, wire 321, switches 104, 105 as adjusted, wire 331, l06 -51, interconnector changeover relay 183, battery, earth.

0142. Auxiliary. (2nd pilot 113.) Battery; relay 183, wire 385, contact and brush 1. 7-625 at half-step, earth.

014.3. Second auxiliary. (2nd pilot 113.) Battery; relay 183, Wire 385; contact and brush 107-4--25, condenser 184, resistance 185, earth.

015. e /hangeover. (2nd-pilot 1-13.) Battery, 2nd pilot magnet 126,normal switch 116, 106-1-13, wire 386, brush 10740 as adjusted, wire 387, points of relay 183, earth.

14.4, Condenser discharge. Earth, resistance 185, condenser 184, brush 107-525 at half step, earth.

lVith pilot 106 at 214, searcher 108 finds an idle final set. 016 and 016.1 charge searcher magnet 128 to advance the brushes of searcher 108 until test relay 186 is charged by 017 and in turn charges magnet 126 by 018, advancing pilot 106 to position.

3-15. Pilot 106 in position 3-15 substitutes earth for relay 186'in. 017, connects wire 331 to 341 and 332 to 342 and becomes inert in the further action of the call served, awaiting release by discharge of holding relay 182 when 013 will have been broken by pilot 103.

016. Interconnector searcher drive. (2nd pilot 214.) Battery, searcher magnet 128,. normal switch 118, 108-15 12, 1064-14, points of test relay 186, earth.

016.1 Interconnector searcher drive. (2nd pilot 214.) Battery, searcher magnet 128, normal switch 118, 108-1525, contacts 13-to23, 106--514, points of test relay 186, earth.

017. Interconnector test. (2nd pilot 214. Earth, helix of test relay 186, 106

of the exchange permits.

The next action is to. adjust the final regisfer or tens switch 402 to the numerical position required, by control of the callsender at the telephone, and then to shift the final pilot 401 as a changeover switch, by joint control. of signal relay 41, register 402 and final changeover relay 193. The method is the same as in adjusting the first register.

The callsender releases signal relay 41 several times rapidly. Relay 41 closes 019 re peatedly which adjusts switch 402- numerically, while by branch circuit 019.1 a" set of impulses is sent to changeover relay Switch 402 also sends by 019.2 and 019.3 two sets of impulses to relay 193, concurrent but out of phase. When relay 193 is finally I released, it closes C20 and charges final pilot magnet 421.

. 019. Numerical impulses. (1st pilot 618; final pilot 1.13.) Earth, 103-.2-18, points of signal relay 41, wire 334, 1031-6, wire 321, switches 104,105 as adjusted, wire 331, 106-1-3, switches 10?, 108 as adjusted, wire 341, 401.4-1, normal switch 412, final register magnet 422, battery, earth.-

019.1. Changeover relay. 618,' final pilot 113.) Earth, 1032-18, points of signal relay 41, wire 334, 103-16, wire 321, switches 104, 105 as adjustecL-wire 331,10613, switches 107, 108 as adjusted, wire 341, 401--11, final changeover relay 193, battery, earth.

019.2. Auxiliary. (Final pilot 113.) Battery, relay 193, wire 366, brush 4026 25 at half-step, earth.

019.3. Second auxiliary. (Final pilot 113.) Battery, relay 193, wire 366, brush 402425, 40151, condenser 194, resistance 195, earth.

020. Ghangeover. (Final pilot 1'-13.) Battery, final pilot magnet 421, normal switch 411, 401113, contact and brush 40240, wire 365, points of final change over relay 193, earth.

019.4. Condenser pilot 113.) v denser 194, 4015-1, brush contact, earth.

Final pilot shifts to 214.

The next action is to adjust the final connector or units switch 403 to the numerical position required, by control of the callsendor at the telephone, and to shift the final pilot 401 as a changeover switch, by joint control of signal relay 41, final switch 403 and final changeover relay 193. The method is the same as in adjusting the final register.

The callsender releases signal relay 41 several times rapidly. Relay 41 closes 021 repeatedly whichadjusts switch 403 numerically, while by branch circuit 019.1. a set of impulses is sent to changeover relay 193. Switch 403 also sends by 021.2 and 021.3 two sets of impulses to relay 193. When relay 193 is released, it closes 022 and charges final pilot magnet 421. i

021. Numerical impulses. (1st pilot 6-18 final pilot 214.) Earth, 103-.2--18, points of signal relay 41, wire 334, 103-1-6; wire 321, switches 104,105 as adjusted, wire discharge, (Final (1st pilot Earth. resistance 195, 0011- .331, switches 106, 1 07, 108 as adjusted, Wire 341, 4014 2, Wire 37 5, normal switch 413, final connector magnet 423, battery, earth.

(121.2. Auxiliary. (Final pilot2-l4.) Battery, relay 193, Wire 366, wire 367, contact and brush 403200, earth.

021.3. Second auxiliary. (Final pilot 2--14.) Battery, relay 193, Wire 366, Wlle 367, contact and brush 403-1925, Wire 368, 401-5-2, condenser 194, resistance195, earth.

C22. Changeover. (Final pilot 2-14.) Battery, final pilot magnet 421, normal switch411,401-1-14, contact and brush 40319-0, Wire 380, wire 365, points 01" changeover relay 193, earth.

C214. Condenser discharge. (Final pilot 2-14.) Earth, lGSlStELIlCBlQQHCOII- denser 194, 4015-2, wire 368,brush 403- 20-25, contact, earth.

Final pilot shifts to 3- 15, sends conn pletion signal 023 to 1st pilot and makes test upon selected line foridle 0r busy condition. At 1st pilot, C23- eharges test relay 44 which locks over (123,1 and by (123.2

passes pilot 103 to positio117---1.0, where 023.3 is formed to pass it to8-20. At the final pilot, if the selected line he "found idle, an idle test circuit G24 charges final pilot magnet 421 and final pilot passes to 44-16,

then C25 charges the final pilot-magnet repeatedly and final pilot passes to position 21, there charging cutoil' relay 1312 by 127. During these acts, the interconnector sets, if any, are inert.

C23. Completion? (1st pilot 6-4.8; final pilot 3-15.)

Battery, relay 44 helix,

Wire 320, 10326, wire 322, switches 104 and 105 as adjusted, wire 332, switches 10.6, 107, 108 as adjusted, 1111'6'342, 401-2 -3, earth. I

023.1. Locking. (Pilot 618.) Battery, relay 44 helix, wire 32 0, 103-713, 103818, Wire 327, relay 44 points, wire 326, 1089-18, 1103-10-18, eartl'i.

(123. 2. Pilot magnet. Battery, pilot magnet 123, nonnal switch 113, 103-14'18, 103-13 18, 1031i2-18,

wire 355, relay 44 points, Wire 308, 10313 --'6, ices-14 t, earth.

(123.3. Pilot magnet. (Pilot 7l,0.)

Battery, pilot magnet 1.23, normal. switch.

113, ma ia-19, 10e' 13 19, 103--1219, earth.

C24. Idle test. (Final pilot 3-15.) Battery, final pilot magnet 421, normal switch 411,'401-1-15, relay 196 points, earth. i

- C25. Final pilot magnet. (Final. pilot 4 '16 to 8-20.) Battery, final pilot magnet 421, normal switch 411', 401--116,

earth.

" There are two speaking positions for pilot 103. If conversation is held when pilot is in position 8-20, meter circuit C32 will be formed and meter 163 will be operated but if conversation is held When pilot is in position 9-21, meter circuit C32 Will not be formed in switch 103.

The selected llne being a free service line, being-a line such as 3713, 3723, 3733,

charges pilot magnet 123 and-first pilot advances to non-metering position 9 21. ll the selected line is not free service, C26 not formed.

C26. Non-metering test. (1st pilot 8 20; final pilot 5-17 to 7-19.) Battery, F 4) line relay 1303 helix, cutoff. relay 313 points, reversed wire on terminals, wire 723, (to Fig. 9) switches 403, 402 as adjusted, 40125, wire 342, switches 108, 10?, 106 as adjiiisted, Wire 332, switches'105, 104 as adjusted, wire 322, 10328, wire 3323, relay 43 helix, earth.

026.1. "-Non-metering test local. (Pilot 8-20.) Battery, resistance 134, wire 336, 1034-8, 10s 11-8, 10s 12 8, Wire 354., charged relay 43 points, wire 356, {103-14- 8, 103-13-8, wire 30S, unehargedrelay 44 points, relay 47 helix, 103---'l 20, earth.

C262. Locking. (Pilot 8 20.) Earth, 103-420, relay 47 helix, relay 47 points,

cl'iargres ringing relay 46 whiehflocks by C232 and. alternating ringing current is passed over (130, through the callhell of the selected line andthrough ringing release relay 43 to earth, the relay 48 being not operated because 01 tlnecondenser in the cal'lbell. circuit. ,1Vl1e1i the receiverot the called line is lifted, relay 43 is operated, releasing relay {6. Answering loop G31 .then is formed cl'iarg'ing relays 43 and 44 and forming 032 to operate nic ter 163 by shunting resistance 134 if: the pilot is in position 8-20. vConversationisover C33 formed from C8 and C31 through condensers 131 and 132.

(328. Ringingstarting. (1st pilot 8 --20;

final pilot 8-20.) Battery, helix of relay 44, points of relay 46',"wire 358, 103-1-8', wire321, switches 104, 105 as adjusted, wire 331, switches 106, 107, 108 as adjusted, wire 341, 401-1-8, earth.

(128.1. Ringing relay. (Pilot 8-20.) Battery, .103-10-8, 10398, wire.355, points of charged relay 44, wire 308, 103- 13-8, 103-14-8, wire 356, points of uncharged relay 43, wire 348, 103-6-20, 103-5-20, helix of ringing relay 46,-e'arth.

(328.2. Locking. Battery, helix of: ring ing relay 46, points of ringing-release relay 48, points of ringing relay 46, earth.

C30. Ringing. (1st pilot 8-20,; final pilot 9-21.) Battery, ringing generator 145, ringing commutator 154; resistance 155, points of charged ringing relay 46, wire 358, 103-1-8, wire" 321, switches 104, 105 as adjusted, wire 331, switches 106,107, 108 as adj usted, wire 341, 401-1-9, switches 402 and 403 adjusted, wire 371.2, line wire 3012, callbell and condenser of telephone set 1562, line wire 3022, wire 3722,'switches 403 and 4.02 as adjusted, 401-2 9, wire342, switches 108, 107, 106 as adjusted, wire 332, switches 105, 104 as adjustedywire 322, 103-2-8, wire 328,1ieliX of relay 48, points ofcharg'ed relay 46, earth.

C31. Answering loop. (1st pilot 8-20 or 9-21; final pilot 9-21.) Battery, h'elix of relay 44, points of discharged relay 46, wire 358, 103-1-8, wire 321, switches 104, 105 as adjusted. wire 33]., switches 106,107, 108 as adjusted, wire 341, switches 401, 402, 403 as adjusted, wire 3712, line wire 3012, telephone set 1562," line-wire 3022, wire 3722, switches 403, 402, 401, wire 342, switches 108, 107, 106 as adjusted, wire switches 105, 104 as adjusted, 'wire 322, 103-2-8, wire 328.-he'lix of relay 43, earth. 1

C32. Meter. (1st pilot 8-20, not 9-21.) Battery, 1113-10-8, 1035-9-23, wire points of relay 44, wire 308, 103-13-8, 103-14-8. wire 356, points of relay 43, wire 354, 1053-12-8, 103118 1021- 4-8, wire 313, switches 102, 101 as adjusted, wire 363, meter 163. earth.

C33. Speaking. (1st pilot8-20; final pilot 9-21.) From line conductors oitfCS to 103-5-8, 103 8 "8, wire .379, condenser 141, wire 376, 103-1-0, and to line conductors of C31 also from line conductors of C8 to 103-6-8, 103-7-8, Wire 3378. condenser 142, wire 377, 103-2-0, and'to line conductors of C31. I I

Should the selected line be busy, then-with final pilot in position 3-15 busy-test circuit C34 would be formed, charging test relay 196 and preventing C24. Final pilot is held in position 3-15, 1st pilot is advanced to circuit C35 is'formed.

C34. Busy test. (Final pilot '3-15.) Battery, resistance 1332, switches'403 and 8-20 by completion signal C23, and. tone switch 113, brushes 103-14 402 as adjusted, 401-3-3, helix of 'test relay 196, earth.

G35. Tone. (1st pilot 8-20; final pilot Earth, tone device 157, points of relay 196, 401-1 3, wire 341; and Lover speaking circuit 033 to calling telephone and to wire 342, 401-2-3, earth.

I divide the action 01 the automatic switches into two parts, first, operation, by which a telephone call is given service, and second restoration by which used switches are returned to their normal condition of waiting, in readiness for service upon a subsequent call.

In using the switches herein described, the method of'restoring each switch. is to advancethe switch electrically to its ultimate position, then to engage its mechanical power source andto restore 'it mechanically to its primary position. If all switches were restoredsimultaneously G7. and C8 might be formed to certain lines through switches 103, 102,101, while other operation circuits might be formed through" other switches. To obviate or reduce this condi tion, I provide method of restoring in which all switches are advanced to render them-independent in operating circuits but dependent in certain restoring circuits, then are restored serially or in groups in such order and in such manner that no operating circuit is formed to any telephone line during the action of restoring, and ultimately are rendered again electrically do pendent in their operating circuits by the final act of restoration. In this method of restoration, the circuits in each restoring switch which might lead to telephone lines are held open in an associated. switch while the restoring switch is ii'eturn'ing to normal. Slow relay49 charged by C8L1Lhas held its armature circuit open during thjerapid operation pf signal relay 41.

Release 18 effected at any time by hanging up the calling telephone. breaking thefcallv Ling loop; C8, releasing relay 41 permanently, thus releasing slow' relay49 to close. pilot release circuit C40, and pilot 103 passes to position 10-22.

08.1. Holding. (Pilot -16 a 9-21. Batteryyhelix of slow relay 49, points of signal relay 41, 103-2-16, earth.

C40. Pilot release. (Pilot' 4-16- to 9-21.) Battery, pilotmagnet 123, normal 25, 1102-13-- to 21, points of 25, 103-3-25, contacts 16 slow relay 49, earth.

Pilot103 in position 10-22 closes switch release circuit C41 which advances switches 101,102, 104 and-105.

C41. Switch release. (Pilot 10-22.) Battery, linefinder magnet 121," normal switch 111, brushes 101-18-25, 101-17- 25, 1011625, contacts-14 to 23', wire- 307,

tery, groupfinder magnet 122, normal switch 112, brushes 102-6--25, 102-5-25, 102-- 425, contacts 12 to22, Wire 310, 103-11- 10, 103-12-10, earth. Also, battery, register magnet 124, normal switch 114, brush. 104-6 25, contacts to 22, wire, 395, 103-2-22, earth. Also, battery, searcher magnet 125, normal switchv 115, brush 105-20-25, contacts 13 to 23, wire 349, l03-422, earth. If switch 104 has not been operated from normal, C41 will not operatethat switch. I Likewise switch 105 and switch 1.01. i

Switches101 and 105 111;].108111101'] 112-24 engage their clutch members. ,Switcbes 1.02 and 104 in position 11-23 jointly close C42 to advance pilot to 11-23 to engage its clutch members.

With the next advancing swing of shaft 231 and hooks 230, switches 101 and105 are restored to'position 0-12, whilethe pilot 103 is restored mechanically to a prenormal position beyond its electrical, normal position, and stops with its brusheson' contacts 0-12. l0uring the reverse movement -01. these switches, noc rcuit is completed to any line because the brushes of switches 1'02 and. 104 connecting circuits from- 103 to 101. and. from103 to 105 areyupon vacant; contacts in-102. and 104. i

Pilot Clutch. (Pilot: 10-22.)

Battery, pilot magnet 1.23, normal switch to position 1-'l3, and completes restoration,

the switches becoming again electrically dependent for operatingcircuits and being again in readiness for further service inresponse'to a calling telephone line.

C43. Switch clutch. (Pilot 0-12.) Battery, register magnet 124:, normal switch 1.04. -c 23, wire 898, 1103-2-12,

earth. Also, gro'upfindermagnet-122,: no];

mal' switch 112, 102-6-23, 102-5-23,

'102-4-23, wire 399 1053- 1-12, earth. It 104 has not been operated from normal, C43 does not operate that switch.

C44. Pilot normalingi (Piloti0-12.) Battery, pilot magnetf123, normal switch 113, 1053-14-12, 103-13-12-103-12-12, wire 392, 102-2-12, wire 393, 1041-41-12, earth. The restoration oil? the 2nd set or inter connector set of switches isasfollows': T

x The release of 1st pi10t1031has brokeh C13 and has released interconneotor holding-re lay 182. Relay 182 closes (1455, charging 2nd pilot magnet-126. repeatedly and pilot 106 advances to 10-22, closing switch release magnet 126, normal switch 116, brush 106- 6- 25, contacts 14 to 21,'points holding relay 182, earth.

C46.- Interconnector. switch magnets. (2nd pilot 10-22.) Battery, 2nd searcher magnet 128, normal switch 118, brush- 108- 15-25, contacts 13 to 23, 106-5-22, points of'relay 186, earth. Also, battery, 2nd register magnet 127, normal switch 117, brush 107-1-25, contacts 13 to 22, 106-4-22, points of'relay 186, earth. a

C47. Interconneotor pilot magnet. (2nd pilot 10-22.) Battery, 2nd pilot magnet 126, normal switch 116, 106-6-22, 107-5- Tilot 106 in position 0-12 closes G48 to 1 restore register 107 and when the registers normal switch closes after restoration of the register, C49 charges test relay 186 which by'ClS (through 106-1-12) charges pilot magnet 126 and pilot steps to its normal position 1-13, asshown in the drawings. (149 does not operate 127 because of resistance of 109 and 186..

I (148. Interconnector register magnet-P (2nd pilot 0-12.) Battery, 2nd register magnet 127, normal switch. 117, 107-1-23, 1'06-4-12, points of relay 186, earth.

C49. Interconnector pilot normalirig. (2nd. pilot 0-12.) Battery, magnet 127, normal switch 117, resistance 109, 107-2- 12, 106-2-12, helix of test relay-186, earth. The interconnector pilot1106 now passes to position 1-13 and closes its test, circuit C13,-which had been open at'107-3-23 while 106 was restoring and at 106-4-0 while 107 was restoring. C13is open also it the detachable part of the switch (body plate 209 and'its brushes) are removed from anycontactbank. H

The restoration of the final set of switches isas follows! The release .of-interconnector. pilot 106 has broken C17 and has released final holding "relay 192. Relay 192 closes C50, charging final pilot magnet 421, repeatedlyand pilot 401 advances to 10-22, closing switch release circuit C51 which advances final connector 403 to 12-24 and finalregister 402 to 11 -23;:register 402 at 11-23 closes circuit C52 and final pilot 401 makes one step to 11--23. Final connector 403 at 12 24 and final pilot 401 at 11 -23 engage their clutch members and both are restored to 0-12. During their movement, telephone line circuits between them are held open by the brushes of the register 402 upon vacant contacts.

C50. Final pilot magnet. (Final. pilot 2-14 to 9--21.) Battery, final-pilot magnet 421, normal switch 411, brush 401-6 25, contacts 14 to 21, points of final holding relay 192, earth. 2 I

C51. Final switch magnets. (Final pilot 10-22.) Battery, final connector magnet 423, normal switch413, brush 403-15 25, contacts 13 to 21, wire 320, 401 5-22, earth. Also, battery, final register magnet 422, normal switch 412, brush 4021-25, contacts 13 to 22, 401422, earth.

052. Final pilot magnet. (Final pilot 10-22.) Battery, final pilot magnet 421, normal switch 411, 4016--22, 402511,

earth.

Final pilot 401 in position 012, closes C58 torestore register 402; and when the registersnormal switch closes after restoration of the register, C54chargesfinaltest relay 196 which by C55 charges final pilot magnet 421 and final pilot steps to its normal position 113, as shown in the drawings.

C53. Final register magnet. (Final pilot 0-12.) Battery, final register magnet 422, normal switch 412, 4021-28, 401 4-12, earth.

C54. Final pilot normaling. (Final pilot 012 Battery, final register magnet 422, normal switch 412, resistance 110, 402 212, 401-2-12, helix of final test relay 196, earth. 1

055. Final pilot magnet. Battery, final pilot magnet 421, normal switch 411, 401- 112, points of relay 196, earth.

Final pilot 401 in position 1-13 closes its test circuit 017 which had beeniopen at 402 -3 23 while-401 was restoring and at 401-60 while 402 was restoring. C17 is open also if the brushes are removed from any contact bark.

Having thus described myv invention, what I claim as new and desire to obtain by U. S. A. Letters Patent is:

1. In an automatic telephone systemya ringing-starting relay, an automaticswitch having busy-testing and speaking positions, and a ringing-starting circuit charging said relay and closed by said switch intermediately of said two positions.

- In an automatic telephone system, a switch, a signal lamp, a relay," a circuit for said signal lamp through points of said relay when said switch is normal and a circuit through switch points in certain positions of said switch other than normal.

an automatic telephone system, a switch, a signal lamp, a relay. a circuit for said signal lamp through points of said relay and points of said switch when said switch normal and a circuit through switch 'pointsin certain positions of said switch other than normal. r

4. In an automatic telephone system, a

switch, a signal lamp, a relay, a circuit for said lamp through points of said relay when said switch is normal, a circuit for said lamp throughswitch points when said switch is in certainpositions other than normal, and

.means-for operating said relay to close said first. lamp circuit when said switch is n0rniarbut busy. a 5. In an automatic telephone exchange, a

set of switches all of which are required to be 1n operative condltion to render any switch available for service, and a test'cir- .cuit for selecting said set'and running serially through all of the switches of the set. 6. Inan automatic telephone exchange, a

.set ofthree switches allof which are required to be in operative condition to render any switch available for service, and a test circuit for selecting said set and run- .iiingserially through all of the switches of the set In-anautomatic telephone exchange, a

set of switches all of which are required to render service, detachable brushes in said switchesand a test circuit for selecting said set and running through detachable brushes in every switch.

8. In. an automatic telephone exchange, a

.set of; switchesall of which are required to render service, detachable brushes in sald switches, a test circuit for selectlng sald set andrunning through detachable brushes in every switch and testing devices for select ing said set and operating to reject said set when any of said brushes are detached.

9. In an automatic. telephone system, a

plurality of levels of switching contacts, a

conductor joining a plurality of contacts, a

brushiconstantly in contact with said contacts and in electrical connection with said conductor in all positions of saidbrush whensaid brush is assembled and a testing circuit :through said brush and testing devices rendered unresponsive to said circuit when said brush is separated from said contacts, by disassembling said switch.

11..In. a telephone system, a line, two

searching switches both connecting. ultimately with said line at the same time, two

7 ing andguard. c'o

, neftwa ammie "S' @1911 we me.

pendently, two test circuits controlling s (1' two ys n ep nd m y, by all .off hibh said switches start 'simuitsn; usly and stop independently n elective p i lisaa e further circuit for advane'iing' "Oriel of sfaid switches to said line. H i I' /1 1 lr h ii yst m, a l e, W9 searching switches, two operating circuits or id wo sw ch s, W9 elay ternal??- g a d two u t ndependshtly,'tw'otst c its n r ll ig. sa l two relays indep n en y; by al of wh ch sa' d sf hbl tar S m tan o sly and tep iiids snd zifily in selective positions; a further as ating r it r tatin 0 B. 0? sa d. Q1195 wail; a d Q f,fli r st ir i ifi s siprins'. a d' s m n nsid a ui nf j l n sa d liel si" :9. I x a dei i tqash a h an uitbhels i 3- 111 t lephi iia ys m a line: W S arch n witches, W-Q' areas-assum o 'f ai Q Wi h'Q PWQ rsl y 'fia srr piiis d We c fiiits in p' d nt y, W0 test circuits controllin relays in: 'd i d tly, y all jwli qh Said sw che m v o e a d top ind psl idn y selective positions and a further cireuif for d anc g ne Qfs i swi ch s, uh fe y Qth' 9 ai Sw t s/ 13 d "159 aid 'inml nd a g d-v ew and 1199 lin as pmt' ns j t y t dete m e. he u mat p si ion of aid asimem Iss wit h- 14 Ina telephone system, 'li'ne, twp ar h n wit hes QPBFEWWQ ri t' s ine eo sm q aiiqus 'ii; means; for "ad/ scm: a tw wi ches sim l aneo s t' prel m ry s ea Po it ons a f r h m ans f r dvancin 01 's" f Tsi fsuit hes f0 swung i. c.

n a e h ne sys mi, a i e, a 1 c t f a d .l lf i P- ak ca i ct f r "Said, inef a m i5fi i sa moving ai si es t ti r ss 'on a ma 4 c sai spe king. an 141 Q d s w furth r m an 'iri'ql j die ers, ferpqsit iis on Of in connection wit I llQg h9B%-- as- 1.6?- In a t le hone syst m; cir iifl r sa di'l n'; 'i for aid l e; a a dw i two l r h u bha b tlii qin d t9 6hnec i e far ca ematia i; im. asf m ving a d s i'tqhes; mfi'ail 'f' i tqip h said switches prelimiiiary 'se ctiv' pdsise s sa d. me ns 1. n

y d spy.

r i r, aafi f ifi rneans including one .conductofsffor es eg onf sa 2139' iii sqia'n i lass-4 8? 1 I a telep e sy te a i e, a line circuit 'for said line; speaking conductors fersaidfline; a guard wire for said line; a li efind lt w m ns, r m vi g S d switch'to a preliminary selective position, sa d, m an n pend n f a pe k and'gulard coiiductors; and further means, including one of said conductors, for moving said switch farther by the same mechanical propelling devices, thereby positioning said switch in connection with said line. i

18 In a telephone systerm a central ofiiee, V

a line, two switches for connecting with said line for contemporaneousservice, circuits whc ly Wi hins i n a o a o a ancs} aid s r tsh sc m ta e usly nd far sfi 'pp' gl sa d switche i iminary ecps 'ltiqa i; a i l i far advancing ne at ai sw ches f tths a5 i ui nc hs sfiid'lih; and a d r d C YQ l t or tbpp 's said a t in'e it ni 'd' sw t h o aid li 1 i t lei hbn y m a e a i-ca a line, switch, eircu i'ts wholly within said central office for advancing said switch and for stopping said switch in a preliminarys'elective position; acircuit for advancingsaid switch further by the saine mechanical prodevices 3 QiilCUit including said line and derived circuit for stop'ping "s'aid switcli'on said line. fl

a tilephone system, a central office, a line, switch; circuits wholly within said central off ce for advancing said switch and for'stopping said switch: in a preliminary seleetivefpositipn; a circuit for advancing said switch-further by the same mechanical propelling devices; a guard-testvcircuit and line-lo'o'p-tes t"circuit "for: "stopping said switch en said'linel 21. In ateleplione system, a linefinder mechanism having two successive searches,

first search independent of the s'peakiiig or -t estiii "eonductor's individual to the line v J .v spur .Hm' l .H,

mechanism having two" successive 2Ld]11Stii'i'efitsftli" first adjustment independentbf the speaking or testing conductors individual t'dtjliljine'," and the seams adjustment dependent upon" t st directly upon the speaking and guard conductors, the'pre linni'n'ary positionsof adjustment being in so e" cases" thefinal positions of adjustment.

Iii "a telephone system, a'line, alinefinder adjustable'te engage said line, means (ioinfiioii toa plurality of lines for adjusting said linefindertoa preliminary position, and circuits fin'dividual to the line for determinii ig the ltimate" adjustment oi said linefi'fider; "said prliininary "adjustment being at'jtiines the ultimate adjustment.

"24'T'Ii1 "afteleplione system," a 'line, other lines, a line finder common to all said lines and having movements of adjustment in but one direction; circuits each common to a. plurality of lines for adjusting said linefinder preliminarily; and test circuits comprising in part conductors individual to said line for readjusting said line finder to engage said line.

25. In a telephone system, a line, other lines, a line finder common to all said lines and having movements of adjustment in but one direction; circuits each common to a plurality of lines for adjusting said linefinder preliminarily, and test circuits comprising in part conductors individual to said line for readjusting said linefinder to a further position of adjustment in engagement with said line.

26. In an electrical switch, a pair of brushes, a pair of contacts connected together, with which said brushes are in engagement when said brushes are at rest, one of said brushes adjusted to engage its contact late in the movement of the brushes toward their position of rest, the other of said brushes adjusted to break engagement from its contact early in the movement of the brushes from their position of rest.

27. In an electrical switch, a pair of brushes, a pair of contacts connected together, with which said brushes are in engagement when said brushes are at rest, one of said brushes adjusted to engage its contact late in the movement of the brushes toward their position of rest, the other of said brushes adjusted to break engagement from its contact early in the movement of the brushes from their position of rest and a circuit including both of said brushes.

Signed by me at Toronto, county of York, and Province of Ontario, Canada.

DAVID S. HULFISH. 

